B1982 – Driver’s Door Unlock Relay Circuit Failure

The ODBII code B1982 indicates a malfunction in the driver’s door unlock relay circuit, which may affect the operation of the door locks.

The severity of ODBII code B1982 is generally considered moderate.

Common Causes For: B1982 Driver’s Door Unlock Relay Circuit Failure

• Faulty driver’s door unlock relay
• Damaged wiring or connectors in the relay circuit
• Short circuit in the relay circuit
• Corroded terminals or connections
• Malfunctioning door lock switch
• Failed body control module (BCM)
• Poor ground connection in the circuit

Common misdiagnosis for B1982 Driver’s Door Unlock Relay Circuit Failure

• Faulty door lock actuator
• Malfunctioning body control module (BCM)
• Wiring issues or shorts in the door harness
• Defective key fob or remote entry system
• Issues with the power door lock switch
• Battery or charging system problems
• Incorrectly programmed key fob
• Faulty door latch assembly
• Software glitches in the vehicle’s computer system
• Ground connection issues

Common Troubleshooting Steps

When dealing with OBD-II code B1982, which indicates a “Driver’s Door Unlock Relay Circuit Failure,” there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:

• Check for Additional Codes: Use an OBD-II scanner to check for any other related trouble codes. Sometimes, multiple codes can provide more context for the issue.
• Inspect the Wiring and Connectors: **Visual Inspection: Look for any damaged, frayed, or corroded wires in the driver’s door harness and the relay circuit.
• **Connector Check: Ensure that all connectors are securely attached and free of corrosion or dirt.
• Test the Door Lock Relay: **Locate the Relay: Find the driver’s door unlock relay in the fuse box or relay panel.
• **Relay Function Test: Swap the relay with a similar one (if available) to see if the problem persists. Alternatively, you can test the relay with a multimeter to check for continuity and proper operation.
• Check the Door Lock Actuator: **Actuator Functionality: Test the door lock actuator to ensure it is functioning correctly. You can do this by applying direct power to the actuator to see if it operates.
• **Resistance Check: Measure the resistance of the actuator to ensure it is within specifications.
• Inspect the Body Control Module (BCM): **BCM Functionality: The BCM controls the door lock functions. Check for any signs of failure or damage.
• **Software Updates: Ensure that the BCM software is up to date, as manufacturers sometimes release updates to fix known issues.
• Check for Ground Issues: Ensure that the ground connections related to the door lock system are secure and free of corrosion. A poor ground can lead to circuit failures.
• Test the Switches: **Driver’s Door Switch: Test the driver’s door lock switch for proper operation. A faulty switch can cause the relay to fail.
• **Continuity Test: Use a multimeter to check for continuity in the switch when pressed.
• Inspect the Fuses: Check the fuses related to the door lock system. A blown fuse can interrupt the circuit and cause the relay to fail.
• Perform a System Reset: After addressing any issues, clear the trouble codes using the OBD-II scanner and see if the code returns after a test drive.
• Consult Repair Manuals or Technical Service Bulletins (TSBs): Look for any specific repair manuals or TSBs related to your vehicle model that may provide additional guidance or known fixes for this issue.1
• Seek Professional Help: If the issue persists after performing these steps, it may be best to consult a professional mechanic or an automotive technician who can perform more advanced diagnostics. By following these steps, you should be able to identify the cause of the B1982 code and take appropriate action to resolve the issue.